I have a 2001 SC1 with a 1.9 SOHC with around 130,000 miles, over the past year or so I have had a very slow coolant leak. (about every 3 months I would have to add a very tiny bit of coolant). Recently I had a low coolant light and I added coolant. I admit I added way too much, the next day I got home and steam was coming out from under the hood. Coolant was flowing out and dripping down on the exhaust (not on the headers) from the back of the block. I jacked it up and it appeared to be running down the back of the block and across the tranny and then was dripping on the exhaust pipe. I figured that I had added too much and had triggered a pressure release. So I checked the coolant, it was normal, no discoloration, nothing. I checked the oil, no coolant in the oil. So I took some coolant out of the tank and let it cool off, the next morning the low coolant light was on, so I added a little and it went off. Went to work, all was ok. About 2 days later it was leaking bad again, in the same spot. I have looked and looked but I couldn't find the spot (i am guessing it is under the intake runners at the head gasket). I then decided I would get some stop leak and put that in (I know...a cheap, quick fix, that probably isn't great, but I don't have a lot of money and thought it might work). I got some BAR'S radiator stop leak that said it was also good for gasket leaks (this was a gold coppery looking substance). I put half the bottle in and followed all the instructions. Still no luck, so I put the rest in and it still was leaking. This leak wasn't that bad, I would have to add coolant about every 2 to 3 days (about 3-4 ounces). Earlier this week, I get to work, I smell coolant. When I get out of work and start it up the light comes on and goes off, start driving and in the middle of the drive the low coolant light comes back on, now I know it is leaking worse because it never has done that before, most of the time the light would come on and when it got up to full pressure and temperature the light would go off, even when it was a little low. I get home and pull off the reservoir cap and the coolant is brownish (which i am not sure if it is oil or is from the stop leak) and the coolant has air bubbles in it. I have been reading the posts and have seen about head gaskets going and also about heads cracking on the drivers side around the 4th cam journal. I know that from 1994 to 1999 the 1.9 SOHC was prone to cracking heads, mine is a 2001, so could that be the problem? I am hoping that it is just a head gasket with a small leak that I made worse by adding too much coolant. Like I said I have no coolant in the oil, no white smoke from the tailpipe (the only white smoke is from coolant burning on the exterior of the exhaust and on the block), about 2,000 miles ago the intake gasket was replaced, I have checked the water pump and I am pretty sure it is not leaking (plus I don't know how the coolant would be making back over to the drivers side on the tranny), the car burns about a quart of oil every 1000 to 1500 miles, and it is not sputtering lagging or having any symptoms of coolant getting in the combustion chamber. When I have owned the car it has never overheated and runs fine. I hope to get some help with this and get an idea of what might be wrong. Like I said the leak appears to be coming from the back of the cylinder head, but I can't see it. I am hoping its not a cracked head, but it may be.
Thanks for your help,
Brian - Ashtabula, OH

PS: I posted about a slamming into all gears a while ago, thank you for all the help on that and I was able to replace the line pressure solenoid without a problem thanks to you guys and this forum...

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If the coolant concentration is not slightly over 50% antifreeze you will have problems. There are hoses back there and there is a small line from the head to the reservoir. Find out what is leaking. Let it cool and wash it off then start it up and let it run in teh drive till you find the leak. It takes a while.

What you are doing now will eventually result in ruining the engine.

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it is definitely not a line or hose, I checked them all today. I'm pretty sure its not the water pump. there was no water around the pulley or around the pump. when i added coolant before it was the 50/50 prediluted universal mix, so I am ok there. when I looked today the leak wasn't bad, but I could smell coolant burning and there was white/blue smoke coming out of the tailpipe on startup, eventually it went away, but I could still smell coolant burning. also it was missing on startup. I'm leaning towards a head gasket, but my main question is could it be a cracked head? Are the 2001 SOHC heads prone to cracking?

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also there was a lot of oil buildup around where the head and block join........ i'm pretty sure its the gasket, but it worries me because people have said that that head gaskets don't go in most cases and the head's crack

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If you think it's the head gasket, run a compression check. You should know then.

What OldNuc was saying about the antifreeze concentration is the stuff in the coolant system. It needs to be above 50% for proper protection, otherwise the water in the coolant will boil. Above 50%, it shouldn't, and somewhere above there is preferred. Adding 50/50 won't do much good if the mixture has gotten below 50%.

I know it was the DOHC that leaked coolant at the intake manifold gasket, but have you changed out your gasket yet (the SOHC vacuum leaks at #1 eventually due to a fold). Just a thought.

...Sasha: 2000 SL1, Manual, 130,500 miles 5-18-2014.

I learn from my experiences. If I screw up, I'm sorry.

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There have been enough cracked SOHC heads to notice. I've agree with OldNuc's theory that it's due to use of 50/50 or other too-low concentrations of coolant. You get a localized "hot spot" hot enough to cause boiling in one area. Check the back of your antifreeze bottles; it's really cheap insurance to get the highest boiling point possible.

There have been enough cracked SOHC heads to notice. I've agree with OldNuc's theory that it's due to use of 50/50 or other too-low concentrations of coolant. You get a localized "hot spot" hot enough to cause boiling in one area. Check the back of your antifreeze bottles; it's really cheap insurance to get the highest boiling point possible.

It's true, I generally like to do a 60/40 mix anyways. I just make sure I add more coolant than water when I'm doing that job. I usually keep straight coolant in my trunk for topoffs if needed.

i'm planning on flushing the system (several times) when i tear into fixing it. my main question is do the 2001 heads crack often? i have been reading all these things about how SOHC engines rarely blow head gaskets and cracked heads from 1994-1999. i am worried that maybe my car might have a cracked head. like i said i am leaning toward a head gasket because of the oil accumulation at the junction of the head and the block and white and blue smoke on start up, although the smoke goes away after running it for a while. it also misses on initial startup and tries to stall and has been using coolant. i cannot tell if there is oil in the coolant because i put stop leak in it like a dummy, but there is no coolant in the oil

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i haven't got a chance to pressure test it yet, because i have barely had time to work on it and i was looking for a quick fix with the leak stop because i thought i just had a minor external leak in the gasket and i thought it might stop it (at least for a while) in reality i probably made it worse. are 2001 heads prone to cracking? if they aren't as prone as the 1994-1999 SOHC heads that i have heard about, i will be about 90% sure it is the gasket and not a cracked head.

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Always the last guy to jump on the bandwagon: that's me!
I have a 1994 Saturn SL with 199,300 miles on it. I've heard it said that Saturns never die, their owners kill them. I've never had a car that lasted so long for $10,000. One rebuilt engine and several repairs later, it's still going.

I had the same issue. I had coolant leaking, and the first thing I wanted to do was trace the source. My first suspicion was one of the hoses from the engine block, since there was coolant all over the place under the hood. I knew the heater core was okay, since there was no smell of coolant inside, and there was no cooling leaking inside. The radiator looked just fine, no sign of leaks there. I also looked around the head gaskets and they were fine too, so using the process of elimination, I deduced it was the water pump, and more specifically the shaft seal. I wiggled the pulley on the water pump, and sure enough, it had more play in it than Schulz did when he tried to buy Tully's. Hence, the spray of coolant that emanated around the water pump pulley while the engine was running.

I bought a Master Pro water pump for $37 which included the gasket, and it cost $150 to install it by my qualified (SAE) mechanic. While he was there, I had him replace the serpentine drive belt at the same time, so I got two-for-one, so to speak. Not a bad deal, considering that it's hard to find SL serpentine drive belts (SL--bottom of the barrel, no A/C, no P/S), so it's a small belt and not one that most parts stores carry in stock.
All in all, the $235 total I spent to replace the water pump and serpentine drive belt was a good investment, considering it was less than the car payments on my Mustang, and I don't have to keep paying every month. I call my lil Saturn the Millennium Falcon: it's the fastest hunk of junk in the galaxy. It's not pretty, it won't get the girls, but it will get you to work and back home every time.

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